I really appreciate your reply.
> I do not understand your comments re < and <=.
> Would you prefer if we had separate rules for < and = ?
> This would just make the algorithm longer. I see
I'm sorry for my obscure writing. Let met put it in this way.
My point is, the spec should define "<" relation, rather than "<="
relation.
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Common sense tells us that "a<=b iff a<b or a=b". I'd like this
proposition to apply to dateTime type, too. (1)
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I assume you agree with the above statement.
The current definition of order-relation of dateTime type (where one has
time zone and the other doesn't) is the following:
> P <= Q if P <= (Q with time zone -14) (2)
> P >= Q if P >= (Q with time zone +14)
> P <> Q otherwise, that is, if (Q with time zone -14) < P < (Q with time zone +14)
The aforementioned common sense implies that " P<=Q iff P<Q or P=Q".
In this case, since one has time zone and the other not, P is never
equal to Q. Therefore, "P<=Q iff P<Q".
This yields a little bit strange definition
P<Q if P<=(Q with time zone-14) (3)
Thus "2001-01-01T14:00:00 > 2001-01-01T00:00Z".
I doubt if this is the intention of WG.
If this is the intention of WG, then the spec should define '<' in this
way rather than defining '<=', because '<' is the fundamental relation
and '<=' is not. The spec mentioned this in section 2.4.1.2.
And you may not define '<=', because the equation (1) is enough.
Note that
P<Q if P<(Q with time zone-14) (4)
Equations (1),(3), and (4) (a common sense, the current definition, and
a natural definition for '<') are inconsistent, although every two of
them is consistent.
I suspect the schema WG doesn't aware that these three are inconsistent.
regards,
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K.Kawaguchi
E-Mail: k-kawa@bigfoot.com